Chemin was one of the pioneers in introducing the Agitated Thin Film Dryer (ATFD) to the industry. ATFD is a heat transfer equipment consisting of a jacketed vessel having a machined surface on the inner side, the rotor assembly consisting of different types of blades mounted on the inner drum. Feed inlet is provided at the top side with proper designed distributor plate. The vapour outlet too is provided on the top side of the shell connected to a cyclone separator.
The feed, which is a high density solution (or mother liquor), enters the shell tangentially and gets spread along the inside surface of the shell into a thin film. The rotor blades keep the film under intense agitation preventing any scale formation. As the heat transfers to the thin film, the feed progressively passes through different phases like liquid, slurry, paste, wet powder and the powder output, finally at the desired dryness.
The vapours produced flow counter current to the film and pass through cyclone separator, further these vapours condense in the indirect contact condenser. The dry powder gets collected in a powder receiver at the bottom, having less than 5% moisture content (depends on the product’s physical properties).